package com.xwh.week2;

import java.math.BigInteger;

public class Practice20 {
    public static void main(String[] args) {
        System.out.println(method(100));
    }
    public static int method(long n){
        BigInteger ans = new BigInteger("1");
        for(long i=2;i<=n;i++){
            String s=i+"";
            ans=ans.multiply(new BigInteger(s));
        }
        String s = ans.toString();
        int sum=0;
        for(int i=0;i<s.length();i++){
            sum+=s.charAt(i)-'0';
        }
    return sum;
    }
}
